Six Minute Push Test: Association With Injury Level, Mobility Disability And Functional Independence In SCI

Abstract

Six-minute walk distance is sensitive to clinically meaningful functional changes and is indicative of mobility disability in the ambulatory. We are currently evaluating if a 6-minute manual wheelchair propulsion test could be a similarly useful tool for the non-ambulatoryg. PURPOSE: To: A) assess relationships between 6-minute manual wheelchair push distance, injury level, self-reported mobility disability and functional independence, and B) compare how 6-minute push distance, injury level, and self-reported mobility disability predict functional independence. METHODS: Twenty-six individuals with a spinal cord injury (SCI, C5-L1) completed a 6-minute manual wheelchair propulsion test (6MPT) in accordance with American Thoracic Society 6-minute walk test standards. Distance travelled (m) was documented. Prior to testing, functional independence was assessed, (SCIM self-care and mobility) and participants rated the difficulty of 4 propulsion and transfer tasks (4 point scale; 1 = no difficulty, 4 = unable to do). Self-reported mobility disability was the sum of the 4 propulsion/transfer questions. Functional independence was the SCIM self-care and mobility sum (SCIM scm), SCIM self-care (SCIM sc), and SCIM mobility (SCIM m) scales. Spearman's rho assessed relationships among the variables. Linear regression determined how injury level, 6MPT, and mobility disability predicted functional independence. (α < 0.05 for all tests). RESULTS: 6MPT, mobility disability and injury level were all strongly correlated with functional independence (all r>0.690) and were all significant predictors of functional independence. As 6MPT distance increased, mobility disability decreased and functional independence increased. 6MPT was a stronger predictor of functional independence than injury level (r2 = 0.79 vs 0.58) CONCLUSION: Preliminary data suggest the 6MPT may be a useful outcome measure for SCI research. It is strongly related to injury level, self-reported mobility disability, and functional independence and appears to better predict functional independence than injury level.